Unforgettable Hawaii Five-0 Guest Stars

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Michael Imperioli guest-starred twice in Season 5 as Odell Martin, a reformed ex-con and attorney who keeps tabs on the criminal underworld from his barbershop. He first appeared in "Powehiwehi" (Episode 14, Season 5) and later in "Kahania" (Episode 19, Season 5). Things got hairy during his second episode, as Martin and McGarrett were attacked trying to protect a young man who was running from the mob. He returned again the next season to help the team with his legal skills in "Ka Pohaku Kiji Pa'a" (Episode 16, Season 6).

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Xzibit dropped in as JC Dekker, another former convict-turned-informer in "Powehiwehi" (Episode 14, Season 5). In this episode, he was badly injured trying to break back into prison and suffered retrograde amnesia. Kono ends up saving his life from a Bulgarian criminal named Roman, and in return he gave her some love-life advice.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Kevin Farley, Jaleel White, and Pauly Shore guest-starred as a trio of tourists, taking a boys weekend to Hawaii to get away from their wives in "Ho'amoano" (Episode 22, Season 5). Their spring break plans got complicated when a dead girl showed up in the bathtub of their hotel room, and, oh yeah... they couldn't remember anything that happened.

It's okay, don't worry. They didn't commit the murder. But they probably won't be eager for a similar vacation anytime soon.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Jon Lovitz gave us a double dose of Barry Burns, who runs a cash-for-gold business and was supposed to be the fence for a diamond heist. He appeared in "Ua helele'i ka hoku" (Episode 17, Season 5) and "Kuka'awale" (Episode 21, Season 5). The diamonds showed up again later in the season, and so did Burns.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Frankie Valli and Carol Burnett played the engaged—and then married—couple of Aunt Deb McGarrett and Leonard Cassano in "Ka Hana Malu" (Episode 8, Season 5). Now that's an A-list couple. 

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Daniel Baldwin played Paul Delano, a corrupt cop—like his brother Frank Delano (who killed Chin Ho Kelly's wife). Appearing in "Poina 'ole" (Episode 12, Season 5), Five-0 thought someone was gunning after Paul because of his connections to a criminal organization that he was supposedly running from inside prison. It turned out he was just running his mouth.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Eric Roberts played Richard Sheridan, a stock broker whose boat had a victim's blood on it in "Wawahi moe'uhane" (Episode 10, Season 5). After some tough interrogation he led the Five-0 to the real killer, his best friend since grade school.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

ATF Agent Kathy Millwood, played by Melina Kanakaredes, followed an arsonist from California to the islands in "Nanahu" (Episode 16, Season 5). She badly wanted to catch him because he torched her house and killed her husband while she was chasing him back in California. With Five-0's help, she was able to complete her journey and finally get a small piece of closure in her life.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

William Forsythe guest-starred as Harry Brown in "Wawahi moe'uhane" (Episode 10, Season 5). When the daughter of a former Coast Guard buddy was murdered, Brown brought his skills as a former private investigator to Hawaii to investigate. The episode was a tribute to film noir and, yes, Forsythe was as awesome as you'd expect.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Robert Knepper guest-starred as Internal Affairs Detective Rex Coughlin in "Pono Kaulike" (Episode 18, Season 5). He had Danny arrested for the murder of drug cartel boss (and CIA agency asset) Marco Reyes, while also booking Chin for tax evasion. Unfortunately, we won't be seeing Knepper as Coughlin again on Hawaii Five-0. He was killed by Gabriel Waincroft at the end of the episode.

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.

Loyal fans of Hawaii Five-0 know all about Terry O'Quinn as retired U.S. Navy Seal Joe White. Recently, he was on "La Po'ino" (Episode 13, Season 5) and "Pono Kaulike" (Episode 18, Season 5). White helped Five-0 track down and stop a deadly virus from being released and helped McGarrett get Danny out of trouble with internal affairs. He's clearly a good friend to have. 

You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.