Survival showdown in 'Send Help' is full of firsts for star Rachel McAdams

Rachel McAdams' maltreated and underappreciated character battles it out with her boss on a desert island in director Sam Raimi's new horror-comedy "Send Help".

McAdams stars as smart but frumpy Linda Liddle, who has long toiled in the strategy and planning department of a consultancy firm, but gets sidelined by her new misogynistic and entitled boss, Bradley (Dylan O'Brien).

Given a final chance to prove her worth, Linda joins Bradley and his band of brothers on a business trip to Bangkok. When their plane crashes in a freak storm, Linda and Bradley are the only survivors and find themselves stranded on a remote island.

A fan of the TV show Survivor, Linda thrives in the new environment, reversing the power dynamics, and tensions between the two soon turn into a battle of wills.

The film, which opens in cinemas globally this week, features gory scenes and blends thriller elements and dark humour in Raimi's hallmark style.

"Linda's been definitely one of the most fun parts I've played", McAdams said at the film's London premiere on Thursday.

"There's just so much to do, from the survival training to being bloodied up like nobody's business. I definitely had a lot of firsts on this film. And after 25 years, you know, that's kind of exciting," the Mean Girls and The Notebook actress said.

O'Brien said the movie, which was shot in Thailand, Australia, and Los Angeles, was less physically demanding for its leads than it appears on screen."I think it was a lot more fun than maybe you're thinking," he said.

"I guess that's the movie magic of it. It looks really miserable, and we're having all this stuff thrown onto us and coming out of us, but it was a blast," he added. 

Raimi, who directed from a script by Damian Shannon and Mark Swift, said he hoped the film would keep audiences on their toes. "I really wanted to follow the screenplay, which suggested it could be a really good audience manipulation film where they just don't know what's happening next," the Evil Dead and Spider-Man filmmaker said.

"It's a lot of fun to be in the crowd when you're invested in the characters and you're trying to figure out which way it's going to go," he added.