He plays the main lead in the remake of the classic 1990 science fiction movie featuring Arnold Schwarzenegger.
He admitted that getting close to Kate was difficult whilst her husband cum director of the film Len Wiseman, was in the same room.
He said: ''All joking aside, kissing her was a bit tricky because you don't kiss another man's woman when he's looking."
''It was one of the most uncomfortable days I've had on a film set and I'm so glad we didn't get past first base in the script. Not that Len was worried, but there was a certain anxiousness in his voice when he called, 'Cut'.''
Colin claims the new version of the movie is straighter than the original, but he hopes people still enjoy it.
He added to the Daily Telegraph newspaper: ''It has things to say, it's very beautiful to look at and hopefully it's clever enough and emotionally engaging enough to keep the audience interested.''